CO2 assimilation (20-25%) and carboxylation efficiency (30-35%) was greater (P < 0.01) in Fragaria chiloensis, clone RCP37 than F. ananassa cv. `Midway'. Both leaf thickness (P < 0.05) and internal mesophyll cell surface area (P < 0.01) was greater in RCP37 than `Midway'. No differences in Rubisco specific activity were observed between the 2 species, whereas Rubisco amount was 40% greater (P < 0.01) and leaf nitrogen per area was 30-35% greater in RCP37 compared to `Midway'. Potential for selection of clones with high photosynthesis by screening for soluble protein will be discussed.